The present invention relates to a telescopic tube with water supply. It is mainly equipped with a minor tube, a major tube that are connected to each other by a tubular coupling device. The tubular coupling device has a registration end and a connecting section, the former is engaged with one end of the minor tube and the latter is engaged with the top end of the major tube. A guard cap is secured to the top end of the major tube which serves to prevent the minor tube from easy disengagement from the major tube in case of excessive extension adjustment. The connecting section of the tubular coupling device has a cone shaped configuration with a spiral thread track defined thereon and terminates in a stop board. A pair of support halves having tapered inner surface are movably registered with the spiral thread track and are outwardly expanded or retracted as moving against the cone shaped connecting section so that the outer surface of the support halves can be urged against the inner side of the major tube to hold the coupling device and the minor tube in place in length adjustment and vice versa for retraction of the telescopic tube. Thus the telescopic tube can be adjusted of its length and secured in place by simple rotation of the major tube and moving the minor tube to make the adjustment easy, speedy and precise.
Referring to FIG. 1, a conventional telescopic tube with water supply is made up of a locking retainer 10, a stopper 20, a coupler 30, a minor tube 40 and a major tube 50. The locking retainer 10 has an internally threaded section 11 and a cone shaped top through hole 12. The stopper 20 is a stepwise form with a through hole 21 at the center and has a small upper section 21 and a large bottom section 22. At the end of the small upper section 21 is defined a peripheral groove 221 for receiving a seal ring 222. There are a pair of peripheral protrusions 231 defined at the top and bottom end of the large bottom section 23 so as to permit a seal ring 232 to be placed in the groove formed therebetween. The coupler 30 is provided with a through hole having two sections having different diameters 31 and 32 so as to form a shoulder 33 at the joint thereof. On the external surface of the large diameter section 31 is disposed a protruded rib area and on the small diameter section 32 is disposed a threaded section 34 with a plurality of flexible claw pieces 35 separated by equally spaced splits 36. The minor tube 40 has a cleaning means 41 at one end which can be a sprinkler or a brush. The major tube 50 has a connector 51 having a connection head 511 with internal threads 512.
As shown in FIG. 2, the assembled telescopic tube can be adjusted of its length by extending or retracting the minor tube 40 with respect to the major tube 50 and then the locking retainer 10 is rotated tight to urge the flexible claw pieces 35 to firmly grasp the minor tube 40 in place. The other end of the major tube 50 is coupled to a water inlet duct so as to permit water to flow into the telescopic tube and discharged via the cleaning means 41.
Such a conventional telescopic tube has the following disadvantages in operation:
1. The locking retainer 10 must be rotated back and forth to make the length adjustment of the telescopic tube tedious and inconvenient.
2. The flexible claw pieces 35 are easily worn out and broken as a result of repeated usage, causing the coupler 30 having worn out thread section 34 unable to lock the minor tube 40 in position.
3. The locking retainer 10 and the coupler 30 are exposed externally and are broken easily in operation.
Therefore, the primary object of the present invention is to provide a telescopic tube with water supply the length of which can be adjusted by simply rotating the major tube and extending or retracting a minor tube and then rotating the major tube further in an opposite direction to get a pair of support halves having a tapered inner face in locking abutment against the major tube in an easy, speedy and precise manner.
Another object of the present invention is to provide a telescopic tube with water supply which is equipped with a tubular coupling device having a cone shaped connecting section on which is defined a spiral thread track. The two support halves each having a retaining blocks in registration with space defined on the gaps of the spiral thread track, and having a tapered inner face are used to get the two support halves fixed in place in abutment with the cone shaped connecting section so that the rotation of the major tube results in the tapered support halves moving upwardly or downwardly along the spiral thread track of the tubular coupling device to hold the minor tube in place with respect to the major tube without abrasion.
One further object of the present invention is to provide a telescopic tube with water supply having the tubular coupling device for coupling the major tube and the minor tube together and the two support halves concealed in the major tube so as to make the appearance appealing in one aspect and to protect the parts from easy damage in practical operation in another aspect.